Acting Veterans Affairs Secretary Sloan Gibson said Wednesday his department has contacted all 1,700 veterans caught up in a hospital wait-list scandal in Phoenix and is working to immediately eliminate long treatment delays nationwide.

WASHINGTON — A far-reaching federal audit of the Department of Veterans Affairs published Tuesday confirmed long treatment delays and deficiencies in its health care system, but found no proof that delays in care caused up to 40 veteran deaths at a Phoenix hospital.

Ethical lapses among top leaders and middle management as well as lack of staff, increased patient demand and an antiquated scheduling system led VA staff to put 3,500 veterans on secret wait lists in Phoenix as a way to hide problems at the facility, according to the audit.

That figure is more than twice as high as the IG reported when its investigation was getting under way in May.

Among those affected in Phoenix, 45 patients — 20 of whom died — “experienced unacceptable and troubling lapses in follow-up, coordination, quality, and continuity of care,” auditors found. In a written response to the IG, newly appointed VA Secretary Bob McDonald said the audit was unable to “conclusively assert” that lack of timely care caused the deaths.

Independent IG auditors conducted the four-month investigation in the wake of reports the VA was cooking patient wait-time records to hide long delays at hundreds of hospitals and clinics across the country. An interim May 28 audit had confirmed many of the allegations outside the Phoenix deaths, finding manipulation of records was systemic throughout the nation’s largest integrated health care system and estimated that at least 1,700 Phoenix vets were in line for care but kept off an official wait list.

The final audit published Tuesday underscored and elaborated on the earlier findings.

“Patients frequently encountered obstacles when patients or their providers attempted to establish care, when they needed outpatient appointments after hospitalizations or emergency department visits, and when seeking care while traveling [to] or temporarily living in Phoenix,” the audit found.

A Phoenix VA doctor turned whistleblower, Sam Foote, ignited a scandal when he reported that up to 40 patients had died due to delayed care. But the IG said it was never provided a list of potential victims. Instead, auditors reviewed 3,409 patient cases from the hospital. Auditors found 45 with serious care issues.

Six patients died among a group of 28 who had treatment delays, and 14 died among another group of 17 patients who experienced substandard medical treatment, according to the report.

“We were unable to assert that the absence of timely quality care caused the deaths of these veterans,” the IG wrote.

In one case, a veteran in his 60s with a history of homelessness came to the hospital and was treated for high levels of blood sugar. An emergency department doctor at the Phoenix VA requested the man have a follow-up primary care appointment within 24 hours but the appointment was never scheduled, the IG reported. The veteran was checked into two other area emergency rooms and eventually died without being seen at the VA hospital again.

Meanwhile, the IG said it opened investigations into employee misconduct and records manipulated at 93 VA facilities and is coordinating on potential criminal charges with the FBI and the Department of Justice.

“These investigations, while most are still ongoing, have confirmed that wait time manipulations are prevalent throughout” the VA health care system, it reported in the audit.

Darrell Richardson, the brother of a Navy veteran who died at the Phoenix VA in 2012, said he is “absolutely furious” about the results of the IG report.

“It’s almost like they’re looking for evidence of murder,” Richardson said. “Their negligence caused death, and it may have caused some prematurely.”

His 65-year-old brother Dennis Richardson was diagnosed with liver cancer but told by VA he would have to wait seven months for a primary care appointment before getting a referral to oncology, he said.

After waiting three months, Dennis went to the VA emergency room because of pain and started chemotherapy, but he was too sick and died, Richardson said.

Sen. Bernie Sanders, I-Vt., who helped author a $16.3-billion VA overhaul law passed this month, said he plans to call a hearing of the Senate Veterans Affairs Committee to review the findings.

“The report by the inspector general on the Phoenix VA provides troubling details about a hospital that failed to meet our nation’s obligation to provide timely, quality health care to veterans,” Sanders said in a statement. “What happened in Phoenix is inexcusable and must never happen again in any VA facility.”

Sanders said he was “relieved, however” that the deaths at the hospital were not conclusively linked to delays in care.

The VA said Tuesday it is working to fix the deep issues within the department, which is the country’s second largest federal agency, by adding staff and sending over 900,000 veterans to private care.

Along with President Barack Obama, McDonald spoke to the American Legion in Charlotte, N.C., on Tuesday, saying the VA needs to win back the faith of veterans. He said the actions of some employees were “at odds with VA’s mission and core values” but that the staff at Phoenix should also be commended.

“I don’t think we can lose sight of the fact that it was at Phoenix, and elsewhere, that employees had the moral courage to do the right thing, take a stand, and make their voices heard about what they saw happening,” he said.

McDonald wrote in the Aug. 18 response letter to the IG that “it is important to note that while OIG’s case reviews in the report document substantial delays in care, and quality of care concerns, OIG was unable to conclusively assert that the absence of timely quality care caused the death of these veterans.”

In an interview with The Associated Press, Deputy VA Sec. Sloan Gibson said that veterans were still waiting too long for care and the department is working to fix the issue.

“They looked to see if there was any causal relationship associated with the delay in care and the death of these veterans and they were unable to find one. But from my perspective, that don’t make it OK,” Gibson said. “Veterans were waiting too long for care and there were things being done, there were scheduling improprieties happening at Phoenix and frankly at other locations as well. Those are unacceptable.”

It's been more than a year since his hearing for Social Security disability benefits, but Gulf War veteran Shawn McMurray still can't get the judge's words out of his mind. "It's tormented me since that day. He took my dignity away. I wasn't proud to be a veteran."